Palladium-catalyzed cross-dehydrogenative coupling between anilides and aromatic aldehydes was achieved under aqueous conditions. A wide variety of the desired benzophenone derivatives was isolated in good to excellent yield. The reaction rate acceleration effect of acid and detergent has been demonstrated. Mechanistic insight has been obtained from quantum chemical calculations.Transition metal-catalyzed direct C À H bond functionalization is one of the most important transformations in recent organic synthetic strategies. [1] Although catalytic transformations based on palladium catalysts are the most frequently utilized oxidative coupling methods in organic syntheses, these reactions usually require harsh conditions (high temperature, long reaction time, necessity of inert atmosphere). Therefore the development of efficient palladium-catalyzed oxidative couplings based on highly active catalyst systems under mild reaction conditions is still highly demanded. Regarding the mechanisms of palladium-catalyzed transformations the presence of monometallic palladium complexes in the catalytic cycle is well accepted. [2] However, very recently the special role and activity of bimetallic palladium species has been discovered and demonstrated in several coupling reactions involving a C À H functionalization step. [3] Be-sides the assessment of the synthetic potential of bimetallic complexes in organic chemistry, a thorough understanding of their working mechanism is also essential. [4] There are several applications of palladium-catalyzed oxidative transformations for the formation of new carbon-carbon bonds via functional group-directed ortho-substitution. [5] Very recently, the synthesis of aromatic ketones from phenylpyridines [6] or acetanilides [7] could be achieved by the palladium-catalyzed oxidative coupling of aldehydes [8] including a C À H activation step.The recently described methodologies of Zhou, [7a] Kwong [7b] and Yu [7c] enable the transformation in toluene at 120 8C, 90 8C, and 40 8C, respectively (Scheme 1.). The latter procedure provides the most efficient conditions for the desired coupling due to the relatively short reaction time under the applied conditions (40 8C, 3 h). Utilization of ketocarboxylic acids instead of aldehydes enables the formation of benzophenone derivatives in a similar palladium-catalyzed coupling at room temperature as it was demonstrated by Ge and co-workers. [9] This transformation works efficiently at room temperature and it has excellent functional group tolerance.It is of note, amongst the previous methodologies depicted on Scheme 1., that only Kwongs proce-A C H T U N G T R E N N U N G dure [7b] offers possibilities for the transformation of ortho-substituted acetanilides.Palladium-catalyzed oxidative coupling of acetanilides with aromatic aldehydes results in 2-acylacetanilides and 2-aminobenzophenone derivatives after hydrolytic cleavage of the amide bond, which are impor-

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A new mild, practical method for the synthesis of aminobenzophenone derivatives through the palladium catalyzed cross-dehydrogenative coupling of anilines with aldehydes in water-SDS mixture is reported. The method involves the protection of aniline followed by its oxidative coupling with the aldehyde and finally the removal of the protecting group in one pot, under aqueous conditions. With these two or three-steps sequences in hand, several Nacetyl and unprotected aminobenzophenone derivatives were isolated in good to excellent yield.Oxidative C -H bond activation is one of the most important topics in recent synthetic organic chemistry.

Benzylic oxidation the presence of iron-surfactant nanocomposite catalyst under aqueous conditions is described. The significant 5 reaction rate acceleration by the presence of anionic surfactants was demonstrated. Several benzylic substrates were efficiently transformed to ketones under mild conditions.Oxidation of methyl or methylene group to carbonyl compounds is one of the most important synthetic transformation in organic chemistry.1 Activated methylene group by neighboring carbonyl moiety can be easily oxidized with selenium dioxide to obtain keto-10 aldehydes and diketones. 2 Benzylic CH 2 group also have high reactivity toward oxidizing agents, and aryl ketones are synthesized with high efficiency. However, to achieve this transformation toxic heavy metal based oxidants such as CrO 3 , 3 Jones reagent, 4 PCC is necessary.5 Development and utilization of environmentally benign catalytic oxidation processes have high relevance in current organic synthesis. Iron based catalyst system for the oxidation of alkanes was introduced by Barton in the early 80's.6 Since its discovery, several developments and extensions of the Gif chemistry have been achieved in the last decades.7 Besides the advantageous application of non-15 toxic iron catalysts for the oxidation of methylene group, the utilization of aqueous tert-butyl hydroperoxide (TBHP) as oxidant in pyridine 8 or in water 9 makes the process even more environmentally friendly. Catalytic transformations under micellar conditions in water can be performed efficiently with the aid of surfactant molecules.10 The formed micelles in aqueous solutions ensures better solubility of non polar organic molecules, and microcompartmentalize reactants which results improved reaction rates due to increased local concentrations inside the micelles. 20Besides the significant influence of surfactant molecules on solubility of organic compounds in water, alkyl sulfates and iron salts are able to build up organized composites with controlled thickness of inorganic layers containing bridged iron ions 11 . The close proximity of iron ions bridged by oxide in non-heme type metalloenzyme models is responsible for oxygen activation and oxidation of alkanes. 12Based on the well defined structure of self assembled iron oxide/surfactant composites we aimed to utilize iron-oxide/sodium dodecylsulfate composite material to mimic the 25 enhanced oxidation ability of diiron complexes. Herein, we describe an efficient protocol for the iron catalyzed benzylic oxidation of organic compounds with iron-surfactant nanocomposites using t BuOOH as oxidant. In our study, we examined several reaction parameters and the effect of surfactants on the reaction rate. TBHP solution is frequently used as applicable oxidant for the iron catalyzed oxidation of benzylic CH 2 group. 8, 9, 13, 14 Therefore we chose aqueous solution of TBHP as oxidant for the preliminary studies. The aqueous reactions were carried out in 5w/w% 30 solution of sodium-dodecylsulfate (SDS) to build up ironoxide/surfactant composit...

Mild Palladium-Catalyzed Oxidative Direct ortho-C-H Acylation of Anilides under Aqueous Conditions. -The rate accelerating effect of long chain anionic detergent and trifluoroacetic acid under aqueous conditions is shown. -(SZABO, F.; DARU, J.; SIMKO, D.; NAGY, T. Z.; STIRLING, A.; NOVAK*, Z.; Adv. Synth. Catal. 355 (2013) 4, 685-691, http://dx.doi.org/10.1002/adsc.201200948 ; Inst. Chem., Eoetvoes Lorand Univ., H-1117 Budapest, Hung.; Eng.) -G. Mueller 32-079